B2C2 FlexCop

The FlexCop is a quite interesting and well-designed PCI interface chipset by B2C2 Inc.. The FlexCop/FlexCop2 family is comprised of the FlexCopII, FlexCopIIb and FlexCopIII variants. It is worthwhile to point out that the FlexCop ASICs have no analog input handling capabilities, but rather are designed strictly for digital receiver applications. These chips contain a flexible MPEG2 Transport Stream interface with hardware PID filters which, if delivery of a complete Transport Stream payload is not desired, allow for the removal of unwanted packets from the stream, and thus reduce the bandwidth utilized when transferred across the host system bus.

PID filtering is most useful in scenarios such as when recording one HD program (typically 14-17Mbps) from a 256-QAM stream (having a demodulated payload ~38.8Mbps), or when recording low resolution program streams from any given Transport Stream. In other scenarios, such as when recording an HD stream encoded with 8-VSB (~19.4Mbps), PID filtering is not as impactive in terms of the relative bandwidth savings, since the saved program usually constitutes most of the original Tranport Stream's bandwidth to begin with. The hardware filters impact may also be limited if in the case of collecting EIT data.

As far we know the FlexCop chipsets contain a Smartcard interface and a CSA Descrambler. As the FlexCop tends to display some quirks in the i2c Protocol interface, the PCI bridge driver thus needs to know which clients are allowed on the bus in order to avoid lockups.